Former NBA star Allen Iverson has abducted his own children ... so says his ex-wife, and now she's begging the court to force Allen to give them back.

Tawanna Iverson just filed legal docs, claiming Allen recently asked for permission to take their five kids on a short vacation to Charlotte, NC from May 22nd-May 26th (and Tawanna agreed) but when May 26th rolled around, the children hadn't been returned.

The kids range in age from 3 to 16 years old.

In the docs, Tawanna says she tried to set up an exchange on June 4th at a neutral location -- a nearby Target store -- but A.I. never showed up.

Tawanna -- who has sole legal and primary physical custody of their children -- now believes Allen never took their kids to Charlotte at all ... and is currently keeping them at a Sheraton hotel in Georgia.

Tawanna claims she's especially concerned because Allen's an alcoholic who drinks around their kids.